The army and its allies had made rapid advances in recent days and pushed through Islamic State lines with the help of heavy artillery and Russian air strikes. The city has been cut off from government areas since 2013 after rebel groups rose up against Syrian President Bashar al-Assad. Islamic State then overran rebel positions and encircled the government enclave and the nearby air base in the city in 2014. During the long siege, high-altitude air drops supplied the city.

The Al Nusrah Front for the People of the Levant, al Qaeda in Iraq's affiliate in Syria, led an assault today that resulted in the takeover of a major dam on the Euphrates River in northern Syria. Additionally, the terror group claimed credit for a suicide assault on an intelligence headquarters in the city of Palmyra. The Al Nusrah Front spearheaded today's assault on the "strategic" dam in Thawra in Raqqa province, according to the Syrian Observatory for Human Rights. The Nusrah Front led "other factions" of the insurgency to take control of Thawra, which "is considered one of the...